Tool-cooling mechanism

ABSTRACT

A tool-cooling mechanism includes a grinding tool. The grinding tool is provided with a converging disc, and the converging disc rotates with the grinding tool to draw external cooling water into the grinding tool for convergence, and then radially conveys the cooling water as converged toward an inner wall of the grinding tool, such that the cooling water can flow to a grinding surface along the inner wall of the grinding tool. The cooling water is allowed to enter via a water inlet and cool the grinding surface smoothly even when the grinding tool is rotating at a high speed, such that the cooling water can be prevented from passing through the grinding tool axially and failing to cool the grinding surface. In addition, the grinding surface is cooled after the cooling water as dispersed and atomized by the rotation of the grinding tool is converged.

CROSS REFERENCE TO THE RELATED APPLICATIONS

This application is the national phase entry of International Application No. PCT/CN2020/111368, filed on Aug. 26, 2020, which is based upon and claims priority to Chinese Patent Applications No. 201910813402.6, filed on Aug. 30, 2019; No. 201921429751.X, filed on Aug. 30, 2019; No. 202010295353.4, filed on Apr. 15, 2020; No. 202020556608.3, filed on Apr. 15, 2020; No. 202020813767.7, filed on May 15, 2020; No. 202010414830.4, filed on May 15, 2020; No. 202010414837.6, filed on May 15, 2020; No. 202020814608.9, filed on May 15, 2020; the entire contents of which are incorporated herein by reference.

TECHNICAL FIELD

The present invention relates to a drilling tool, and in particular, to a tool-cooling mechanism.

BACKGROUND

Among grinding tools, a trepanning drill, a cup/disc grinding wheel, an annular grinding disc, and the like are all common rotary grinding tools or cutters that perform grinding/cutting by an end surface. The trepanning drill, also known as a material drawing drill, is a special cutter or grinding tool that works on solid materials in a ring-cutting fashion, and may draw reusable barstock in a workpiece needing to be machined. The cup/disc grinding wheel is a binding grinding tool that solidifies and binds, via a binding agent, a grinding material into an annular working ring linked to a substrate, and has certain strength. The annular grinding disc is analogous to the cup/disc grinding wheel with a great ring width.

The aforesaid grinding tools shall be cooled during the working process. In a case where equipment adopting the grinding tool does not have an internal cooling supply structure, the prior art generally provides various types of water passing holes on a substrate of the grinding tool, such that water is pressed to enter an inner cavity of the grinding tool via the water passing holes and thus flows through cutting edges of the grinding tool to cool a grinding surface.

The grinding tool may further include grinding tools of a cup-wheel type, the working surface of which is an annular end surface working ring. During the working process, the workpiece may cover the whole port of the grinding wheel, or cover part of the port of the grinding wheel in different directions, which may make it difficult to apply the cooling water to the inner cavity of the grinding wheel from the port of the grinding wheel. Under this case, a simple way is to apply the water at the cutout in the outer diameter of the grinding wheel to form an external cooling mode. However, due to a centrifugal force, it is difficult for the cooling water to act from the outer diameter to the inner diameter, which restricts the cooling effect and causes a poor cooling effect especially at the portion of the grinding wheel against the inner diameter. During the processing at a high rotating speed, an “airflow barrier” may be formed on inner and outer sides and the end surface of the grinding wheel, which may greatly affect the external cooling effect. In order to improve this situation, the following technical solutions are adopted currently.

The first fashion in the prior art is to provide a cup grinding wheel 22 as shown in FIG. 30. Several large holes, i.e., water passing holes 2201 shown in FIG. 30, are provided on the end surface of the cup grinding wheel (substrate), and the cooling water is shot into the inner cavity of the grinding wheel via the large holes. In this fashion, the problem in the entering of the cooling water at a low rotating speed can be solved. The water enters the inner cavity of the grinding wheel from the plurality of water passing holes 2201, and part of the cooling water in contact with the grinding wheel may perform cooling under the action of a centrifugal force along the water slot or grinding surface in a direction from the inner diameter to the outer diameter. For the cooling water entering the inner cavity of the grinding wheel in this fashion, some may pass through the grinding wheel, resulting in waste, and some may never be subjected to the centrifugal force, resulting in waste well. According to this fashion, the entering ratio of the cooling water may decrease when the grinding wheel is rotating at a high speed, and the cooling water may be easily “atomized” during the process of entering the cavity of the grinding wheel, thereby affecting and reducing the cooling effect.

The second fashion in the prior art is to provide a cup grinding wheel 23 as shown in FIG. 31. A large number of small inclined holes, i.e., water passing holes 2301 in FIG. 31, are provided on a portion of the end surface of the substrate proximate to the outer diameter, and a water storing space structure is further provided for assistance. The cooling water may enter the inner cavity of the grinding wheel after sequentially passing through the water storing space and the water passing holes 2301, and thus perform cooling under a centrifugal force along the water slot or grinding surface in a direction from the inner diameter to the outer diameter. In this fashion, the circulating area of the water holes is small and the water intake is limited. In addition, the entering ratio of the cooling water may be reduced during the rotation at a high speed, thereby further restricting the cooling effect.

SUMMARY

In summary, in order to overcome the defects of the prior art, the technical problem to be solved by the present invention is to provide a tool-cooling mechanism when grinding equipment does not have an internal cooling supply structure.

The technical solution for solving the aforesaid technical problem is to provide a tool-cooling mechanism, which includes a grinding tool. The grinding tool is internally provided with a converging disc, and the converging disc rotates with the grinding tool to draw external cooling water into the grinding tool for convergence, and then radially conveys the cooling water as converged toward an inner wall of the grinding tool, such that the cooling water can flow to a grinding surface along the inner wall of the grinding tool.

The present invention has following beneficial effects. The cooling water can enter through a water inlet and cool the grinding surface smoothly even when the grinding tool is rotating at a high speed, such that the cooling water can be prevented from passing through the grinding tool axially and failing to cool the grinding surface. In addition, the grinding surface is cooled after the cooling water as dispersed and atomized by the rotation of the grinding tool is converged, such that the cooling can be achieved during an entire process even when the grinding tool is rotating at the high speed.

The following improvements may further be made on the present invention based on the aforesaid technical solution.

Furthermore, the grinding tool is provided with a water inlet at a top thereof for pouring the cooling water therein, and the converging disc is fixed within the grinding tool at a corresponding position below the water inlet.

Furthermore, several blades are included, wherein the several blades are distributed on the converging disc and form a vortex that draws the external cooling water into the grinding tool with rotation of the grinding tool.

The beneficial effect as achieved by adopting the aforesaid further solution is that the vortex for drawing the cooling water via the water inlet is formed by the blades under the rotation of the grinding tool.

Furthermore, the blades are distributed around an outer periphery of the top of the converging disc.

Furthermore, fastening bolts for fastening the blades and the converging disc at corresponding positions within the grinding tool are included, wherein the fastening bolts are provided in correspondence with the blades one by one; and

the fastening bolts sequentially pass from top to bottom through a sidewall of the top of the grinding tool corresponding to an outer periphery of the water inlet, the corresponding blades, and the converging disc.

The beneficial effect as achieved by adopting the aforesaid further solution is that the blade, in addition to having the function of drawing water, further serves as a connector to fix the converging disc to the grinding tool.

Furthermore, an outer peripheral edge of the converging disc extends outwardly to a position close to the inner wall of the grinding tool, such that a guiding gap is formed between the converging disc and the inner wall of the grinding tool to restrict the cooling water from flowing downward along the inner wall of the grinding tool.

The beneficial effect as achieved by adopting the aforesaid further solution is to reduce the influence of the “airflow barrier” and thus to increase the utilization ratio of the cooling water.

Furthermore, the converging disc is provided coaxially with the water inlet, the converging disc has a greater radial dimension than that of the water inlet, and a water storing area for storing the cooling water temporarily is formed between the converging disc and the sidewall of the top of the grinding tool corresponding to the outer periphery of the water inlet.

The beneficial effect as achieved by adopting the aforesaid further solution is to facilitate converging of the water in an atomized state and to increase the water intake.

Furthermore, the blades are all provided spirally in a same spiral direction.

The beneficial effect as achieved by adopting the aforesaid further solution is to improve the adsorption force for drawing the cooling water via the water inlet.

Furthermore, the converging disc is provided with a connecting structure at the top thereof, and the connecting structure passes upwards through the water inlet along an axial direction of the grinding tool and connects to grinding equipment.

The beneficial effect as achieved by adopting the aforesaid further solution is to achieve the connection between the grinding tool and the grinding equipment.

Furthermore, several blades are included, wherein the grinding tool is provided with an open area in a middle portion thereof and an equipment hole in a center of a bottom surface thereof for connecting to external equipment; an annular end surface of an outer periphery of the grinding tool is a grinding surface; the converging disc is provided in the open area of the grinding tool and is removably connected to the bottom surface of the grinding tool; the converging disc includes a first disc body and a water inlet hole allowing the cooling water to enter the grinding tool; an outer edge of the first disc body extends to an intersection between a sidewall and the bottom surface of the grinding tool; the water inlet hole is provided at a center of the first disc body and is coaxial with the equipment hole, and the first disc body is inclined in a direction from the water inlet hole to the intersection between the sidewall and the bottom surface of the grinding tool to form an annular inclined surface structure; a gap allowing the cooling water to pass through is arranged between the outer edge of the first disc body and the sidewall and the bottom surface of the grinding tool; the several blades are disposed between the first disc body and the bottom surface of the grinding tool and are arranged at intervals on the first disc body along a circumferential direction, and the several blades divide the gap into a plurality of converging channels.

Furthermore, the several blades respectively extend radially in a direction from the water inlet hole to the outer edge of the first disc body and are formed integrally with the first disc body.

Furthermore, extending lines of the several blades do not pass through a center point of the first disc body, and form a vortex shape.

Furthermore, an airflow stopping collar is further included, wherein the airflow stopping collar encircles an outer edge of an upper surface of the first disc body, and an airflow isolating channel for isolating airflow is formed between the airflow stopping collar and the inner wall of the grinding tool.

Furthermore, the airflow stopping collar is parallel to the sidewall of the grinding tool and extends from the sidewall towards the bottom surface.

Furthermore, the airflow stopping collar is inclined from outside to inside in a direction from the sidewall to the bottom surface of the grinding tool.

Furthermore, a circular connecting disc provided with a connecting hole in a center thereof for connecting the external equipment is further included, wherein the connecting hole is provided coaxially with the equipment hole, each of the several blades is provided with a notch on a bottom surface thereof, and each of the notches extends outward from an inner sidewall of the blade to a position near an outer sidewall thereof and forms a circular groove along a circumferential direction, the connecting disc being placed inside the circular groove.

Furthermore, a main spindle screw is further included, wherein the main spindle screw sequentially passes through the connecting hole of the connecting disc and the equipment hole of the grinding tool and is threaded to a main spindle of the external equipment.

Furthermore, a blade connecting bolt is further included, wherein the first disc body is provided with a blade screw hole at a position corresponding to the blade, and the grinding tool has a screw slot at a position corresponding to the blade screw hole, an internal thread is provided in the screw slot, and wherein the blade connecting bolt passes through the blade screw hole and is threaded into the screw slot to connect the grinding tool and converging disc as one.

Furthermore, a plurality of impellers is further included, wherein the grinding tool is provided with an open area in a bottom end thereof, and a surface encircling an outer edge of the bottom end of the grinding tool is a grinding surface; a connecting block having a cylindrical shape is provided at a center of a top end of the grinding tool; an annular hollowed-out area encircling the connecting block is provided at the top end of the grinding tool; and the several impellers are placed within the annular hollowed-out area, connected transversely between the connecting block and an outer edge of the top end of the grinding tool, and distributed at intervals along a circumferential direction of the connecting block;

wherein the converging disc is provided in the open area of the grinding tool, and includes a connecting post and a second disc body which are coaxial with the connecting block, wherein the connecting post is formed as a hollow cylinder with an open lower end, and has an upper end removably connected to a bottom surface of the connecting block; the second disc body encircles an outer periphery of the connecting post; an inner edge of the second disc body is integrally formed with an outer wall of a bottom end of the connecting post, and an outer edge of the second disc body extends to the sidewall of the grinding tool to form an annular surface structure; and a gap allowing the cooling water to pass through is arranged between the outer edge of the second disc body and the sidewall and the bottom surface of the grinding tool.

Furthermore, the outer edge of the second disc body extends horizontally to the sidewall of the grinding tool and is formed as an annular plane.

Furthermore, the outer edge of the second disc body extends to an intersection between the sidewall and the bottom surface of the grinding tool, and the second disc body is inclined upward in a direction from the connecting post to the intersection between the sidewall and the bottom surface of the grinding tool, and is formed as an annular inclined surface.

Furthermore, the converging disc further includes an airflow stopping ring that encircles an outer edge of the second disc body, and an airflow isolating channel for isolating airflow is formed between the airflow stopping ring and the inner wall of the grinding tool.

Furthermore, the airflow stopping ring is parallel to the sidewall of the grinding tool and extends from the sidewall towards the bottom surface.

Furthermore, the airflow stopping ring is inclined from top to bottom in a direction approaching the sidewall of the grinding tool.

Furthermore, a main spindle connecting bolt is further included, wherein main spindle screw holes are provided coaxially at a top end of the connecting block and at the center of the connecting post; the main spindle connecting bolt sequentially passes from bottom to top through the spindle screw holes of the connecting post and the connecting block and is threaded to a main spindle of the external equipment, thereby locking the converging disc and the grinding tool to the external equipment.

Furthermore, the grinding tool is a trepanning drill, a cup grinding wheel, a disc grinding wheel or an annular grinding disc.

The beneficial effect as achieved by adopting the aforesaid solution is that the mechanism that changes the external cooling mode to the internal cooling mode can be applied to different rotating grinding tools or cutters in the case where the grinding equipment does not have an internal cooling supply structure, and thus has a wide range of application.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an overall structural diagram of Embodiment 1;

FIG. 2 is a sectional view of FIG. 1;

FIG. 3 is a structural diagram of a grinding tool;

FIG. 4 is a structural diagram of a converging disc;

FIG. 5 is a structural schematic diagram of a cooling structure according to Embodiment 2;

FIG. 6 is a planar sectional view of the cooling structure without a connecting disc according to Embodiment 2;

FIG. 7 is a three-dimensional sectional view of the cooling structure without a connecting disc according to Embodiment 2;

FIG. 8 is a planar sectional view of the cooling structure with a connecting disc according to Embodiment 2;

FIG. 9 is a three-dimensional sectional view of the cooling structure with a connecting disc according to Embodiment 2;

FIG. 10 is a distribution diagram for blades extending lines of which do not pass through a center point according to Embodiment 2;

FIG. 11 is a top view for blades extending lines of which do not pass through the center point according to Embodiment 2;

FIG. 12 is a top view for blades extending lines of which pass through the center point according to Embodiment 2;

FIG. 13 is a side view for blades according to Embodiment 2;

FIG. 14 is a schematic diagram showing flowing of cooling water in the cooling structure according to Embodiment 2;

FIG. 15 is a top view of a grinding tool according to Embodiment 3;

FIG. 16 is a schematic diagram of a second disc body according to Embodiment 3;

FIG. 17 is a schematic diagram of one second disc body according to Embodiment 3;

FIG. 18 is a sectional view of the one second disc body according to Embodiment 3;

FIG. 19 is a sectional view of the one second disc body in a cup grinding wheel according to Embodiment 3;

FIG. 20 is a schematic diagram for flowing of cooling water in the one second disc body according to Embodiment 3;

FIG. 21 is a schematic diagram of another second disc body according to Embodiment 3;

FIG. 22 is a sectional view of the another second disc body according to Embodiment 3;

FIG. 23 is a sectional view of the another second disc body in a cup grinding wheel according to Embodiment 3;

FIG. 24 is a schematic diagram for flowing of the cooling water in the another second disc body according to Embodiment 3;

FIG. 25 is a schematic diagram of an airflow stopping ring according to Embodiment 3;

FIG. 26 is a schematic diagram for flowing of the cooling water at the airflow stopping ring according to Embodiment 3;

FIG. 27 is a schematic diagram of blades according to Embodiment 3;

FIG. 28 is a structural schematic diagram of a cup grinding wheel and a diverting cover according to the prior art of Embodiment 2;

FIG. 29 is a schematic diagram for flowing of the cooling water in the cup grinding wheel according to the prior art of Embodiment 2;

FIG. 30 is a structural schematic diagram of a cup grinding wheel according to a first fashion of the prior art of Embodiment 3;

FIG. 31 is a schematic structural diagram of a cup grinding wheel according to a second fashion of the prior art of Embodiment 3;

FIG. 32 is a three-dimensional diagram of a tooth ring according to Embodiment 4;

FIG. 33 is a top view of FIG. 32;

FIG. 34 is a sectional view of FIG. 33 along A-A;

FIG. 35 is a top view of the tooth ring with a mounted cooling mechanism; and

FIG. 36 is a sectional view of FIG. 35 along B-B.

In the accompanying drawings, the members as represented by respective reference signs are listed as follows.

1 Grinding tool; 2 water inlet; 3 converging disc; 4 blade; 5 water storing area; 6 fastening screw; 7 guiding gap; 8 connecting structure; 9 equipment hole; 10 water inlet hole; 11 airflow stopping collar; 12 connecting disc; 13 main spindle screw; 14 main spindle; 15 blade connecting screw; 16 blade screw hole; 17 connecting block; 18 connecting post; 19 annular hollowed-out area; 20 airflow stopping ring; 21 main spindle connecting screw; 101 diverting cover; 301 first disc body; 302 second disc body; A weak area of airflow barrier; B airflow isolating channel; 22 one cup grinding wheel of the prior art; 23 another cup grinding wheel of the prior art; 2201 water passing hole according to a first fashion of the prior art; 2301 water passing hole according to a second fashion of the prior art; 24 substrate; 25 tooth piece; 26 water passing groove; 27 inner ring body; 28 outer ring body; 29 water passing hole; and 30 impeller.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The principles and features of the present invention will be described below in conjunction with the accompanying drawings, and examples given are intended to explain the present invention only and are not intended to limit the scope of the present invention.

Embodiment 1

A grinding tool 1 in this embodiment is a trepanning drill.

As shown in FIGS. 1-3, a tool-cooling mechanism includes a grinding tool 1 and a water inlet 2. The water inlet 2 is disposed at the top of the grinding tool 1 for pouring cooling water into the grinding tool 1. The grinding tool 1 is internally provided with a converging disc 3, and the converging disc 3 rotates with the grinding tool 1 to draw external cooling water into the grinding tool 1 for convergence, and then radially conveys the cooling water as converged toward an inner wall of the grinding tool 1, such that the cooling water flows to a grinding surface along the inner wall of the grinding tool 1.

As shown in FIG. 4, the cooling mechanism further includes blades 4. The converging disc 3 is fixed within the grinding tool 1 (namely, the trepanning drill) at a corresponding position below the water inlet 2. The converging disc 3 is provided with a connecting structure 8 at the top thereof, and the connecting structure 8 passes upwards through the water inlet 2 along an axial direction of the grinding tool 1 and then is connected to a main spindle of grinding equipment (i.e., a drilling machine), thereby enabling the trepanning drill 1 to rotate under the driving of the drilling machine. Several blades 4 are provided and distributed on the converging disc 3 and form a vortex with rotation of the trepanning drill 1. Preferably, the blades 4 are all provided spirally in the same spiral direction, which enhances the vortex effect that occurs after the rotation, and thus increases the adsorption force for drawing the cooling water via the water inlet. The converging disc 3 and the blades 4 may rotate simultaneously when the trepanning drill 1 rotates for processing and drawing out the material. The blades 4 are inclined at a preset angle relative to the horizontal plane, that is, the blades 4 are provided spirally. Thus, the rotating blades 4 may drive the air to form a vortex having a pushing effect on the cooling water below the water inlet 2, thereby pushing the cooling water to pass through an airflow barrier as formed by the high-speed rotation at the water inlet 2 smoothly, and drawing the cooling water into the trepanning drill 1 (the rotating converging disc 3 can also draw the cooling water). This allows the cooling water to enter smoothly via the water inlet 2 and cool the grinding surface even when the trepanning drill 1 is rotating at a high speed, and thus ensures that the cooling can be achieved during the entire process even when the trepanning drill 1 is rotating at the high speed for processing. In addition, the converging disc 3 may axially block the cooling water entering the grinding tool 1, prevent the cooling water from passing through the grinding tool 1 axially and failing to cool the grinding surface, and converge the cooling water as dispersed and atomized by the rotation of the grinding tool. In the present invention, the water inlet 2 may be designed into a completely unobstructed circular water inlet based on the converging disc 3 and the blades 4, and an orifice of a water outlet pipe for supplying the cooling water may directly enter an inner cavity of a substrate after passing through the grinding tool 1 via the water inlet 2, thereby breaking the airflow barrier at the water inlet 2. In the prior art, through holes or the like are formed on the substrate of the grinding tool, such that the cooling water as poured on the surface of the substrate enters the inner cavity of the substrate via the through holes for external cooling. Regardless of whether the through holes are provided on the upper surface or the outer circumference of the substrate, the orifice of the water outlet pipe for supplying the cooling water cannot enter the inner cavity of the substrate because the grinding tool may rotate with the water outlet pipe if the water outlet pipe port extends to the inner cavity from the through holes, which is a concept of an internal cooling structure. The present invention achieves the cooling effect of the internal cooling mode via an “external cooling” structure.

The blades 4 are distributed on the converging disc 3 in such a fashion that the blades 4 are distributed around an outer periphery of the top of the converging disc 3. In correspondence to the fashion above in which the blades 4 are distributed, fastening screws 6 that correspond to the blades 4 one by one are adopted to fix the converging disc 3 and the blades 4 in the trepanning drill 1. That is, the fastening screws 6 sequentially pass from top to bottom through a sidewall of the top of the trepanning drill 1 corresponding to an outer periphery of the water inlet 2, the corresponding blades 4, and the converging disc 3. Thus, the blades 4, in addition to having the function of drawing water, further serve as a connector to fix the converging disc 3 to the grinding tool.

An outer peripheral edge of the converging disc 3 extends outwardly to a position proximate to the inner wall of the trepanning drill 1, such that a guiding gap 7 is formed between the converging disc 3 and the inner wall of the trepanning drill 1 to restrict the cooling water from flowing downward along the inner wall of the trepanning drill 1. After being drawn into the trepanning drill 1, entering the inner cavity of the grinding tool and being converged to the converging disc 3, the cooling water is pushed by the blades 4, the centrifugal force and other effects and driven to move toward the outer circumference of the converging disc 3 (i.e., the inner wall of the grinding tool 1), such that the cooling water is hardly thrown out of the trepanning drill 1 via the water inlet 2. Under the action of the guiding gap 7, the cooling water moving to the inner wall of the grinding tool flows downward along the inner wall and is finally thrown out via the grinding surface at the bottom of the trepanning drill 1 under the action of the pressure, gravity and centrifugal force. Thus, the cooling effect of the internal cooling fashion is achieved, the contact area between the cooling water and the trepanning drill 1 is increased, and the utilization rate of the cooling water is increased.

The converging disc 3 is provided coaxially with the water inlet 2, the converging disc 3 has a greater radial dimension than that of the water inlet 2, and a water storing area 5 for storing the cooling water temporarily is formed between the converging disc 3 and the sidewall of the top of the trepanning drill 1 corresponding to the outer periphery of the water inlet 2. The cooling water as drawn by the blades 4 may be firstly stored temporarily in the water storing area 5 that provides a temporary storing cavity for the cooling water. Thus, the intake cooling water may be prevented from flowing backwards via the water inlet 2 with the rotation of the trepanning drill 1 due to the incapability of being stored, which facilitates converging of the water in an atomized state and finally increases the water intake.

Embodiment 2

As shown in FIGS. 28 and 29, a cup grinding wheel which is a current grinding tool is provided with a diverting cover, and FIG. 29 shows the flowing of cooling water that is injected via a water inlet of the cup grinding wheel. Due to the high-speed rotation of the cup grinding wheel, an “airflow barrier” is formed at inner and outer walls and on the end surface of the cup grinding wheel, a “weak area of the airflow barrier” is formed at an intersection between the bottom surface and the inner wall of the cup grinding wheel 1, and a “strong area of the airflow barrier” is formed at a port area of the grinding wheel. For the cooling water sprayed to the inner wall of the cup grinding wheel via a water outlet of the diverting cover, part of the cooling water is “atomized” by the airflow while passing through the “airflow barrier”, and part of the cooling water splashes because of hitting the inner wall of the grinding wheel and then is dispersed by the airflow. Thus, due to the “dispersing” and “atomizing” effect of the “airflow barrier”, part of the cooling water is dispersed and loses the cooling effect, which greatly reduces the amount of cooling water entering a grinding surface of the cup grinding wheel and causes the water supply to the grinding surface to be insufficient, thereby failing to ensure the comprehensive cooling during the machining process.

The cooling mechanism of the present invention will be described below in detail. The grinding tool 1 in this embodiment is a cup grinding wheel.

As shown in FIGS. 5 to 14, the cooling mechanism further includes several blades 4. The grinding tool 1 is provided with an open area in a middle portion thereof and an equipment hole 9 in a center of a bottom surface thereof for connecting to external equipment. An annular end surface of an outer periphery of the grinding tool 1 is a grinding surface. The converging disc 3 is provided in the open area of the grinding tool 1 and is removably connected to the bottom surface of the grinding tool 1. The converging disc 3 includes a first disc body 301 and a water inlet hole 10 allowing the cooling water to enter the grinding tool 1. An outer edge of the first disc body 301 extends to an intersection between a sidewall and the bottom surface of the grinding tool 1. The water inlet hole 10 is provided at the center of the first disc body 301 and is coaxial with the equipment hole 9, and the first disc body 301 is inclined in a direction from the water inlet hole 10 to the intersection between the sidewall and the bottom surface of the grinding tool 1 to form an annular inclined surface structure. A gap allowing the cooling water to pass through is arranged between the outer edge of the first disc body 301 and the sidewall and the bottom surface of the grinding tool 1. The several blades 4 are disposed between the first disc body 301 and the bottom surface of the grinding tool 1 and are arranged at intervals on the first disc body 301 along a circumferential direction, and the several blades 4 divide the gap into a plurality of converging channels.

It should be understood that the outer edge of the first disc body 301 is more proximate to the bottom surface of the cup grinding wheel than the inner edge, as shown in FIG. 6.

It should be understood that the gap between the outer edge of the first disc body and the substrate of the cup grinding wheel forms a converging channel, also called a converging action area that includes flowing water and water droplets. When the flowing water and water droplets pass through the converging action area and reach the converging channel, a large number of water droplets are gathered into a water current, and the water current becomes a water stream (beam current) under the action of a centrifugal force, the water stream herein referring to water flowing along the inner wall.

During the high-speed rotation of the cup grinding wheel, the converging disc 3 and the several blades 4 enable the cooling water beam as supplied to quickly stick to the inner wall of the cup grinding wheel, and pressurize and accelerate the cooling water inside the cup grinding wheel, thereby helping the cooling water beam to pass through the “airflow barrier” area via the “weak area of the airflow barrier”, and reducing the splashing of the cooling water beam as caused by hitting the inner wall. The airflow stopping collar 11 reduces the influence of the airflow on the cooling water in the airflow isolating channel, prevents the cooling water from being dispersed or losing the cooling effect, and greatly increases the amount of cooling water entering the grinding surface of the cup grinding wheel, such that the comprehensive cooling can be ensured during the machining process.

As shown in FIGS. 10 and 13, the several blades 4 respectively extend radially in a direction from the water inlet hole 10 to the outer edge of the first disc body 301 and are formed integrally with the first disc body 301.

The blades 4 are provided on the converging disc body, and when the cup grinding wheel rotates, the blades 4 change the direction of the cooling water and push the cooling water to the inner wall of the grinding wheel via the water inlet hole 10, such that the cooling water pushed to the inner wall may be effectively acted on by the centrifugal force. Then, the cooling water affixed to the inner wall cools the grinding surface along the inner wall or via the water slot, such that the water is supplied in a direction from the inner diameter to the outer diameter of the cup grinding wheel, and the comprehensive cooling of the grinding surface is ensured.

As shown in FIG. 11, extending lines of the several blades 4 do not pass through a center point of the first disc body 301, and form a vortex shape.

In another case, as shown in FIG. 12, the extending lines of the several blades 4 pass through the center point of the first disc body 301, and form a stellate shape. The blades 4 in the vortex shape and the blades 4 in the stellate shape push the cooling water, which helps the cooling water to break the blocking of the “airflow barrier” and effectively affix to the inner wall of the cup grinding wheel, thereby improving the effective rate of the cooling water.

As shown in FIG. 8, an airflow stopping collar 11 is further included. The airflow stopping collar 11 encircles an outer edge of an upper surface of the first disc body 301, and an airflow isolating channel for isolating airflow is formed between the airflow stopping collar 11 and the inner wall of the grinding tool 1 (cup grinding wheel).

As shown in FIG. 8, the airflow stopping collar 11 is parallel to the sidewall of the grinding tool 1 and extends from the sidewall towards the bottom surface.

As shown in FIG. 14, the airflow stopping collar 11 is inclined from outside to inside in a direction from the sidewall to the bottom surface of the cup grinding wheel.

Specifically, the airflow stopping collar 11 may be provided parallel to the inner wall of the cup grinding wheel, or may be inclined.

As shown in FIGS. 6 and 14, the airflow stopping collar 11 may isolate the “airflow isolating channel (shown as B in FIG. 14)” and enable the cooling water to form a water beam, such that the water beam may flow against the inner wall of the cup grinding wheel under the action of the centrifugal force to prevent the cooling water from being dispersed or losing the cooling effect.

As shown in FIGS. 8 and 9, a circular connecting disc 12 provided with a connecting hole in the center thereof for connecting the external equipment is further included. The connecting hole is provided coaxially with the equipment hole 9, each of the several blades 4 is provided with a notch on a bottom surface thereof, and each of the notches extends outward from an inner sidewall of the blade 4 to a position near an outer sidewall thereof and forms a circular groove along a circumferential direction, the connecting disc 12 being placed inside the circular groove.

The connecting disc 12 is capable of strengthening the connection between the cup grinding wheel and the converging disc 3 and preventing disconnection.

Furthermore, a main spindle screw 13 is further included. The main spindle screw 13 sequentially passes through the connecting hole of the connecting disc 12 and the equipment hole 9 of the grinding tool 1 and is threaded to a main spindle 14 of the external equipment.

Specifically, as shown in FIG. 6, another connecting fashion is implemented without the connecting disc 12, and the connecting disc 12 is replaced by a washer. The main spindle screw 4 sequentially passes through the washer and the equipment hole 9 of the cup grinding wheel and is threaded to the main spindle 14 of the external equipment.

It should be understood that no notch is provided on the blades 4 when the washer is adopted, and the blades 4 are abutted against the bottom surface of the cup grinding wheel, such that the connecting disc 12 and the cup grinding wheel can be connected quickly and securely to the main spindle 14 of the external equipment.

A blade connecting bolt 15 is further included. The first disc body 301 is provided with a blade screw hole 16 at a position corresponding to the blade 4, the grinding tool 1 has a screw slot at a position corresponding to the blade screw hole 16, and an internal thread is provided in the screw slot. The blade connecting bolt 15 passes through the blade screw hole 16 and is threaded into the screw slot to connect the grinding tool 1 and converging disc 3 as one.

Specifically, when no connecting disc 12 is provided, the connection fashion is as follows. The blades 4 are abutted against the bottom surface of the cup grinding wheel, and the first disc body 301 is provided with a screw hole at a position corresponding to the blade 4. The cup grinding wheel has a screw slot at a position corresponding to the blade screw hole, and an internal thread is provided in the screw slot. The blade connecting bolt 15 passes through the blade screw hole and is threaded into the screw slot to connect the cup grinding wheel and the converging disc as one. There may be a plurality of blade connecting bolts 15 which are distributed around the several blades 4.

It can be seen that in this embodiment, the blades 4 are not only members pushing the cooling water, but also members connecting the cup grinding wheel (substrate).

Specifically, while the converging disc 3 is provided, the cooling structure further includes a connecting disc connecting bolt and the connection fashion is as follows. The converging disc 3 is provided with a screw hole, and the blade 4 is provided with a screw slot. The connecting disc connecting bolt passes through the screw hole of the connecting disc 3 and is threaded into the screw slot, thereby connecting the connecting disc 3 and the blades 4 as one. There may be a plurality of converging disc connecting bolts which are distributed around the several blades 4.

Specifically, the blade 4 with the screw slot is thicker than the blade 4 without the screw slot to prevent the blade 4 with the screw slot from breaking.

In addition, it is possible to prevent the members from detaching from each other when the grinding wheel is rotating at a high speed.

As shown in FIG. 14, the converging disc 3 in the present invention, instead of the diverting cover 101 provided in the conventional cup grinding wheel, is of greater significance than the diverting cover 101 for enhancing the working condition of the grinding surface when the cup grinding wheel is rotating at an ultra-high speed.

The cooling water can be strongly pushed. The blades 4 of the converging disc 3 are in the stellate shape or the vortex shape, and push the cooling water strongly to the inner wall of the cup grinding wheel at a place where the airflow barrier is weakest, and enable the cooling water to affix to the inner wall, thereby applying the cooling water to the grinding surface along the inner wall or via the water passing slot by making the most of the centrifugal force (minimizing the influence of airflow).

The influence of the airflow barrier can be reduced. In the conventional water supplying mode, the place where the cooling water is disposed has the strongest airflow barrier, which is the most influential drawback and causes the cooling water to be less effective. The converging disc 3 however can overcome the drawback by feeding the cooling water from the weak area of the airflow barrier (shown as A in FIG. 14) to the area favorable to the cooling of the cup grinding wheel, and the airflow stopping collar 11 reduces the influence of the airflow on the cooling water in the airflow isolating channel. For the water in a stream flowing state, it is affixed to the inner wall and pushed by the centrifugal force to act on the grinding area from inside to outside, thereby preventing the cooling water from being dispersed or losing the cooling effect and achieving a stronger cooling effect.

The utilization rate of the cooling water can be increased. The cooling water in the traditional cup grinding wheel is sprayed, and the cooling water has a higher possibility of being atomized. However, the gap between the converging disc 3 and the cup grinding wheel forms a converging channel, which changes the flow path of the cooling water and allows the cooling water to be in a stream flowing state, thereby reducing the possibility of being atomized and improving the utilization rate of the cooling water.

Embodiment 3

The grinding tool may further include grinding tools of a cup-wheel type, the working surface of which is the annular end surface working ring. During the working process, a workpiece may cover the whole port of the grinding wheel, or cover part of the port of the grinding wheel in different directions, which may make it difficult to apply the cooling water to the inner cavity of the grinding wheel from the port of the grinding wheel. Under this case, a simple way is to apply the water at the cutout in the outer diameter of the grinding wheel to form an external cooling mode. However, due to the centrifugal force, it is difficult for the cooling water to act from the outer diameter to the inner diameter, which restricts the cooling effect and causes a poor cooling effect especially at the portion of the grinding wheel against the inner diameter. During the processing at a high rotating speed, an “airflow barrier” may be formed on inner and outer sides and the end surface of the grinding wheel, which may greatly affect the external cooling effect. In order to improve this situation, following technical solutions are adopted currently.

The first fashion in the prior art is to provide a cup grinding wheel 22 as shown in FIG. 30. Several large holes, i.e., water passing holes 2201 shown in FIG. 30, are provided on the end surface of the cup grinding wheel (substrate) and the cooling water is shot into the inner cavity of the grinding wheel via the large holes. In this fashion, the problem in the entering of the cooling water at a low rotating speed can be solved. The water enters the inner cavity of the grinding wheel from the plurality of water passing holes 2201, and part of the cooling water in contact with the grinding wheel may perform cooling under the action of a centrifugal force along the water slot or grinding surface in a direction from the inner diameter to the outer diameter. For the cooling water entering the inner cavity of the grinding wheel in this fashion, some may pass through the grinding wheel, resulting in waste, and some may never be subjected to the centrifugal force, resulting in waste well. According to this fashion, the entering ratio of the cooling water may decrease when the grinding wheel is rotating at a high speed, and the cooling water may be easily “atomized” during the process of entering the cavity of the grinding wheel, thereby affecting and reducing the cooling effect.

The second fashion in the prior art is to provide a cup grinding wheel 23 as shown in FIG. 31. A large number of small inclined holes, i.e., water passing holes 2301 in FIG. 31, are provided on a portion of the end surface of the substrate proximate to the outer diameter, and a water storing space structure is further provided for assistance. The cooling water may enter the inner cavity of the grinding wheel after sequentially passing through the water storing space and the water passing holes 2301, and thus perform cooling under the action of a centrifugal force along the water slot or grinding surface in a direction from the inner diameter to the outer diameter. In this fashion, the circulating area of the water holes is small and the water intake is limited. In addition, the entering ratio of the cooling water may be reduced during the rotation at a high speed, thereby further restricting the cooling effect.

The cooling mechanism of the present invention will be described below in detail. The grinding tool 1 in this embodiment is a cup grinding wheel.

As shown in FIGS. 15 to 16, the cooling mechanism further includes a plurality of impellers 30. The grinding tool is provided with an open area at a bottom end thereof, and a surface encircling an outer edge of the bottom end of the grinding tool is a grinding surface. A connecting block 17 having a cylindrical shape is provided at the center of a top end of the grinding tool 1; an annular hollowed-out area 19 encircling the connecting block 17 is provided at the top end of the grinding tool 1; and the several impellers 30 are placed within the annular hollowed-out area 19, connected transversely between the connecting block 17 and an outer edge of the top end of the grinding tool 1, and distributed at intervals along a circumferential direction of the connecting block 17.

The converging disc 3 is provided in the open area of the grinding tool 1, and includes a connecting post 18 and a second disc body 302 which are coaxial with the connecting block 17. The connecting post 18 is formed as a hollow cylinder with an open lower end, and has an upper end removably connected to a bottom surface of the connecting block 17. The second disc body 302 encircles an outer periphery of the connecting post 18; an inner edge of the second disc body 302 is integrally formed with an outer wall of a bottom end of the connecting post 18; and an outer edge of the second disc body 302 extends to the sidewall of the grinding tool 1 to form an annular surface structure. A gap allowing the cooling water to pass through is arranged between the outer edge of the second disc body 302 and the sidewall and the bottom surface of the grinding tool 1.

When the cup grinding wheel rotates at a high speed, the several impellers 30 generate a pushing force and draw the injected cooling water into the cavity of the cup grinding wheel. The converging disc 3 prevents the cooling water from traversing directly from the bottom, and the flow path of the cooling water entering the inner cavity is changed under the action of the converging disc 3. Most of the water flow is forced to flow through the inner wall of the cup grinding wheel, and then performs cooling under the action of the centrifugal force along the grinding surface (or water slot) of the cup grinding wheel from the inner diameter to the outer diameter. Thus, the utilization rate of the cooling water is increased and the cooling effect is greatly improved. In addition, the chip removal can be facilitated, and a large amount of cooling water beam may pass through the “airflow barrier” area via the “weak area of the airflow barrier”, which effectively weakens the negative effect of the “airflow barrier”, realizes the changing from the external cooling mode to the internal cooling mode, and achieves the cooling of the whole grinding surface during the entire process.

As shown in FIGS. 17-20, the outer edge of the second disc body 302 extends horizontally to the sidewall of the grinding tool 1 and is formed as an annular plane.

The second disc body 302 prevents the cooling water from traversing directly from the bottom and changes the path of the cooling water, which forces a large amount of cooling water to flow through the inner wall of the grinding wheel, and thus increases the utilization rate of the cooling water.

As shown in FIGS. 21-24, the outer edge of the second disc body 302 extends to an intersection between the sidewall and the bottom surface of the grinding tool 1, and the second disc body 302 is inclined upward in a direction from the connecting post 18 to the intersection between the sidewall and the bottom surface of the grinding tool 1, and is formed as an annular inclined surface.

The second disc body 302 in the form of the annular inclined surface can reduce the splashing of the cooling water beam as caused by hitting the inner wall and greatly increase the amount of cooling water entering the grinding surface of the cup grinding wheel.

As shown in FIGS. 25 to 27, the converging disc 3 further includes an airflow stopping ring 20 that encircles an outer edge of the second disc body 302, and an airflow isolating channel for isolating airflow is formed between the airflow stopping ring 20 and the inner wall of the grinding tool 1.

The airflow stopping ring 20 reduces the influence of the airflow on the cooling water in the airflow isolating channel, which prevents the cooling water from being dispersed or losing the cooling effect, and thus ensures a comprehensive cooling during the machining process.

Specifically, the airflow stopping ring 20 is parallel to the sidewall of the grinding tool 1 and extends from the sidewall towards the bottom surface.

Specifically, the airflow stopping ring 20 is inclined from top to bottom in a direction approaching the sidewall of the grinding tool 1.

Specifically, the airflow stopping ring 20 may be provided parallel to the inner wall of the cup grinding wheel, or may be inclined.

The inclined airflow stopping ring 20 may isolate the “airflow isolating channel (shown as B in FIG. 26)” and enable the cooling water to form a water beam, such that the water beam may flow against the inner wall of the cup grinding wheel under the action of the centrifugal force to prevent the cooling water from being dispersed or losing the cooling effect.

The following beneficial effects are achieved by providing second disc body 302 and the airflow stopping ring 20.

The influence of the airflow barrier can be reduced. In the conventional water supplying mode, the place where the cooling water is disposed has the strongest airflow barrier, which is the most influential drawback and causes the cooling water to be less effective. The converging disc 3 however can overcome the drawback by feeding the cooling water from the weak area of the airflow barrier (shown as A in FIG. 26) to the area favorable to the cooling of the cup grinding wheel, and the airflow stopping ring 20 reduces the influence of the airflow on the cooling water in the airflow isolating channel. For the water in a stream flowing state, it is affixed to the inner wall and pushed by the centrifugal force to act on the grinding area from inside to outside, thereby preventing the cooling water from being dispersed or losing the cooling effect and achieving a stronger cooling effect.

The utilization rate of the cooling water can be increased. The cooling water in the traditional cup grinding wheel is sprayed, and the cooling water has a higher possibility of being atomized. However, the gap between the converging disc 3 and the cup grinding wheel forms a converging channel, which changes the flow path of the cooling water and allows the cooling water to be a stream flowing state, thereby reducing the possibility of being atomized and improving the utilization rate of the cooling water.

As shown in FIG. 27, a main spindle connecting bolt 21 is further included. Main spindle screw holes are provided coaxially at a top end of the connecting block 17 and at the center of the connecting post 18. The main spindle connecting bolt 21 sequentially passes from bottom to top through the spindle screw holes of the connecting post 18 and the connecting block 17 and is threaded to a main spindle of the external equipment, thereby locking the converging disc 3 and the grinding tool 1 to the external equipment.

The main spindle connecting bolt 21 enables the converging disc 3 and the cup grinding wheel to be mounted together on the external equipment.

As shown in FIG. 27, a plurality of blades 4 is further included and is disposed between the second disc body 302 of the converging disc 3 and a top surface of the grinding tool 1 (the cup grinding wheel). The plurality of blades 4 is arranged at intervals on the second disc body 302 in a circumferential direction, and divides the gap between the second disc body 302 and the grinding tool 1 (the cup grinding wheel) into a plurality of converging channels.

After testing, the utilization rate of the cooling water as drawn by a single blade 4 is only 27%, and can reach more than 90% under the combined action of several blades 4 and the second disc body 302 of the converging disc 3.

The role of the impellers 30 in Embodiment 3 is primarily to generate the pushing force to draw the injected cooling water into the cavity of the cup grinding wheel.

The role of the plurality of blades 4 in Embodiment 3 is primarily to generate a radial pushing force to push the cooling water to the outer wall of the cup grinding wheel.

The overall advantages of the cooling structure in Embodiment 3 are as follows.

1. The cooling structure can fit various rotation speeds and increase the entering ratio of the cooling water into the inner cavity of the grinding wheel with an increase in the rotation speed, thereby greatly increasing the utilization rate of the cooling water.

2. The cooling structure can change the external cooling mode to the internal cooling mode, thereby cooling the whole grinding surface during the entire process.

3. The cooling structure can effectively weaken the negative effect of the “airflow barrier”.

4. The inclined converging disc forms an annular inclined surface structure, and under the combined action of the centrifugal force and pushing force from the blades and impellers, the cooling water is converged into a stream and accelerated to break the “airflow barrier”, thereby greatly increasing the effective rate of the cooling water.

5. The cooling structure can help to remove chips.

6. Since the cooling water entering the inner cavity is mostly forced to flow against the inner wall of the cup grinding wheel, the cooling water can perform cooling under the action of the centrifugal force along the water slot or grinding surface from the inner diameter to the outer diameter. Thus, the cooling effect is greatly improved.

7. The cooling structure is simple and easy to achieve.

Specifically, the grinding tool 1 may also be a trepanning drill, a disc grinding wheel or an annular grinding disc.

Embodiment 4

The cooling mechanism according to the present invention may further be applied to the following cup grinding wheel capable of splitting the cooling water into two branches.

As shown in FIGS. 32-34, the cup grinding wheel above includes an annular substrate 24, several tooth pieces 25 and a diverting structure. The tooth pieces 25 are arranged at intervals along the circumferential direction and fixed to a side of the substrate 24 to form a tooth ring. The side of the tooth ring distal from the substrate 24 is an annular working surface, and two adjacent tooth pieces 25 are spaced apart to form a water passing slot 26 for conveying the cooling water to the working surface. The diverting structure is fixed to the tooth ring and diverts the cooling water into two branches. The first branch is conveyed to an outer side area of the working surface through the inner side of the water passing slot 26 under the action of the centrifugal force generated by the rotation of the substrate 24. The second branch is conveyed to the inner side area of the working surface through the outer side of the water passing slot 26 under the action of the centrifugal force generated by the rotation of the substrate 24, and is further conveyed from the inner side area to the outer side area of the working surface under the blocking of the workpiece to be processed. The diverting structure includes an outer ring body 27 and an inner ring body 28. The outer ring body 27 is fixed to the outer side of the tooth ring, and the inner ring body 28 is fixed to the inner side of the tooth ring. A water passing hole 29 is provided on the sidewall of the inner ring body 28 at a position corresponding to the water passing slot 26, which thus forms the first branch from the water passing hole 29 to the outer side area of the working surface through the water passing slot 26, and the second branch from the inner sidewall of the inner ring body 28 to the inner side area of the working surface.

As shown in FIGS. 35 and 36, the tooth ring is fixed at the bottom of the cooling mechanism according to the present invention, and the blades 4 in the cooling mechanism may also form a vortex for pushing the cooling water with the rotation of the cup grinding wheel, which helps the cooling water to pass through the airflow barrier formed by the high-speed rotation at the water inlet 2. The cooling water as drawn is converged to the converging disc 3, and may be pushed by the blades 4 and driven by the centrifugal force or other effects on the converging disc 3 to move downwards along the inner wall of the tooth ring and toward the outer periphery of the converging disc 3, such that the cooling water can hardly move upward and be thrown out of the cup grinding wheel 1 via the water inlet 2. After the cooling water reaches the inner wall of the tooth ring, the cooling water entering the tooth ring may be blocked by the inner ring body 28 under the action of the centrifugal force generated by the high-speed rotation of the cup grinding wheel, thereby preventing all the cooling water from entering the water passing slot 26. Due to the water passing hole 29 in the inner ring body 28, the cooling water within the tooth ring is divided into two branches (shown by arrows in FIG. 34).

The first branch has a following flow path. A part of cooling water enters the water passing slot 26 from the inner side of the tooth ring through the water passing hole 29. The cooling water that enters the water passing slot 26 flows against the inner wall of the outer ring body 27 along the axial direction of the tooth ring and moves towards the outer side area of the grinding surface under the blocking of the outer ring body 27, and then cools the outer side area of the grinding surface.

The second branch has a following flow path. Another part of cooling water flows against the inner wall of the inner ring body 28 along the axial direction of the tooth ring and moves toward the inner side area of the grinding surface under the flow restricting effect of the water passing hole 29, then cools the inner side area of the grinding surface and flows toward the outer side area of the grinding surface after cooling the inner side area of the working surface.

The above description is only the preferred embodiments of the present invention, and is not intended to limit the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be regarded as within the protection scope of the present invention. 

What is claimed is:
 1. A tool-cooling mechanism, comprising: a grinding tool, wherein the grinding tool is internally provided with a converging disc, and the converging disc rotates with the grinding tool to draw external cooling water into the grinding tool for convergence, and then radially conveys the cooling water as converged toward an inner wall of the grinding tool, wherein the cooling water flows to a grinding surface along the inner wall of the grinding tool.
 2. The tool-cooling mechanism according to claim 1, wherein a top of the grinding tool is provided with a water inlet for pouring the cooling water in the grinding tool, and the converging disc is fixed within the grinding tool at a corresponding position below the water inlet.
 3. The tool-cooling mechanism according to claim 2, further comprising: a plurality of blades, wherein the plurality of blades are distributed on the converging disc and form a vortex with rotation of the grinding tool, wherein the vortex draws the external cooling water into the grinding tool.
 4. The tool-cooling mechanism according to claim 3, wherein the plurality of blades are distributed around an outer periphery of a top of the converging disc.
 5. The tool-cooling mechanism according to claim 4, further comprising: fastening bolts for fastening the plurality of blades and the converging disc at corresponding positions within the grinding tool, wherein the fastening bolts are provided in correspondence with the plurality of blades one by one; and the fastening bolts sequentially pass from top to bottom through a sidewall of the top of the grinding tool corresponding to an outer periphery of the water inlet, the corresponding blades, and the converging disc.
 6. The tool-cooling mechanism according to claim 2, wherein an outer peripheral edge of the converging disc extends outwardly to a position close adjacent to the inner wall of the grinding tool, wherein a guiding gap is formed between the converging disc and the inner wall of the grinding tool to restrict the cooling water from flowing downward along the inner wall of the grinding tool.
 7. The tool-cooling mechanism according to claim 2, wherein the converging disc is provided coaxially with the water inlet, a radial dimension of the converging disc is greater than a radial dimension of the water inlet, and a water storing area for storing the cooling water temporarily is formed between the converging disc and the sidewall of the top of the grinding tool corresponding to the outer periphery of the water inlet.
 8. The tool-cooling mechanism according to claim 3, wherein the plurality of blades are all provided spirally in a same spiral direction.
 9. The tool-cooling mechanism according to claim 2, wherein a top of the converging disc is provided with a connecting structure, and the connecting structure passes upwards through the water inlet along an axial direction of the grinding tool and connects to grinding equipment.
 10. The tool-cooling mechanism according to claim 1, further comprising: a plurality of blades, wherein an open area is provided in a middle portion of the grinding tool, and an equipment hole is provided in a center of a bottom surface of the grinding tool for connecting to external equipment; an annular end surface of an outer periphery of the grinding tool is the grinding surface; the converging disc is provided in the open area of the grinding tool and is removably connected to the bottom surface of the grinding tool; the converging disc comprises a first disc body and a water inlet hole, wherein the water inlet hole allows the cooling water to enter the grinding tool; an outer edge of the first disc body extends to an intersection between a sidewall and the bottom surface of the grinding tool; the water inlet hole is provided at a center of the first disc body and is coaxial with the equipment hole, and the first disc body is inclined in a direction from the water inlet hole to the intersection between the sidewall and the bottom surface of the grinding tool to form an annular inclined surface; a gap allowing the cooling water to pass through is arranged between the outer edge of the first disc body and the sidewall and the bottom surface of the grinding tool; and the several plurality of blades are disposed between the first disc body and the bottom surface of the grinding tool and are arranged at intervals on the first disc body along a circumferential direction, and the plurality of blades divide the gap into a plurality of converging channels.
 11. The tool-cooling mechanism according to claim 10, wherein the plurality of blades respectively extend radially in a direction from the water inlet hole to the outer edge of the first disc body and are formed integrally with the first disc body.
 12. The tool-cooling mechanism according to claim 10, wherein extending lines of the plurality of blades do not pass through a center point of the first disc body, and form a vortex shape.
 13. The tool-cooling mechanism according to claim 10, further comprising: an airflow stopping collar, wherein the airflow stopping collar encircles an outer edge of an upper surface of the first disc body, and an airflow isolating channel for isolating airflow is formed between the airflow stopping collar and the inner wall of the grinding tool.
 14. The tool-cooling mechanism according to claim 13, wherein the airflow stopping collar is parallel to the sidewall of the grinding tool and extends from the sidewall towards the bottom surface.
 15. The tool-cooling mechanism according to claim 13, wherein the airflow stopping collar is inclined from outside to inside in a direction from the sidewall to the bottom surface of the grinding tool.
 16. The tool-cooling mechanism according to claim 10, further comprising: a circular connecting disc, wherein a connecting hole is provided in a center of the circular connecting disc for connecting the external equipment, and the connecting hole is provided coaxially with the equipment hole; a bottom surface of each of the plurality of blades is provided with a notch, and the notch extends outward from an inner sidewall of each of the plurality of blades to a position adjacent to an outer sidewall of each of the plurality of blades and forms a circular groove along a circumferential direction; and the connecting disc is placed inside the circular groove.
 17. The tool-cooling mechanism according to claim 16, further comprising: a main spindle screw, wherein the main spindle screw sequentially passes through the connecting hole of the connecting disc and the equipment hole of the grinding tool and is threaded to a main spindle of the external equipment.
 18. The tool-cooling mechanism according to any one of claims 10-17, further comprising: a blade connecting bolt, wherein the first disc body is provided with a blade screw hole at a position corresponding to each of the plurality of blades, the grinding tool has a screw slot at a position corresponding to the blade screw hole, and an internal thread is provided in the screw slot, wherein the blade connecting bolt passes through the blade screw hole and is threaded into the screw slot to connect the grinding tool and converging disc as one.
 19. The tool-cooling mechanism according to claim 1, further comprising: a plurality of impellers, wherein an open area is provided in a bottom end of the grinding tool, and a surface encircling an outer edge of the bottom end of the grinding tool is the grinding surface; a connecting block having a cylindrical shape is provided at a center of a top end of the grinding tool; an annular hollowed-out area encircling the connecting block is provided at the top end of the grinding tool; and the plurality of impellers are placed within the annular hollowed-out area, the plurality of impellers are connected transversely between the connecting block and an outer edge of the top end of the grinding tool, and the plurality of impellers are distributed at intervals along a circumferential direction of the connecting block; the converging disc is provided in the open area of the grinding tool, and the converging disc comprises a connecting post and a second disc body, wherein the connecting post and the second disc body are coaxial with the connecting block, wherein the connecting post is formed as a hollow cylinder with an open lower end, and the connecting post has an upper end removably connected to a bottom surface of the connecting block; the second disc body encircles an outer periphery of the connecting post; an inner edge of the second disc body is integrally formed with an outer wall of a bottom end of the connecting post, and an outer edge of the second disc body extends to a sidewall of the grinding tool to form an annular surface structure; and a gap allowing the cooling water to pass through is arranged between the outer edge of the second disc body and the sidewall and a bottom surface of the grinding tool.
 20. The tool-cooling mechanism according to claim 19, wherein the outer edge of the second disc body extends horizontally to the sidewall of the grinding tool and is formed as an annular plane.
 21. The tool-cooling mechanism according to claim 19, wherein the outer edge of the second disc body extends to an intersection between the sidewall and the bottom surface of the grinding tool, and the second disc body is inclined upward in a direction from the connecting post to the intersection between the sidewall and the bottom surface of the grinding tool, and is formed as an annular inclined surface.
 22. The tool-cooling mechanism according to any one of claims 19-21, wherein the converging disc further comprises an airflow stopping ring, wherein the airflow stopping ring encircles the outer edge of the second disc body, and an airflow isolating channel for isolating airflow is formed between the airflow stopping ring and the inner wall of the grinding tool.
 23. The tool-cooling mechanism according to claim 22, wherein the airflow stopping ring is parallel to the sidewall of the grinding tool and extends from the sidewall towards the bottom surface.
 24. The tool-cooling mechanism according to claim 22, wherein the airflow stopping ring is inclined from top to bottom in a direction approaching the sidewall of the grinding tool.
 25. The tool-cooling mechanism according to claim 19, further comprising: a plurality of blades between the second disc body of the converging disc and a top surface of the grinding tool, wherein the plurality of blades are arranged at intervals on the second disc body in a circumferential direction, and the plurality of blades divide the gap between the second disc body and the grinding tool into a plurality of converging channels.
 26. The tool-cooling mechanism according to any one of claims 19-21 and 23-25, further comprising: a main spindle connecting bolt, wherein a first main spindle screw hole and a second main spindle screw hole are provided coaxially at a top end of the connecting block and at a center of the connecting post, respectively; and the main spindle connecting bolt sequentially passes from bottom to top through the second main spindle screw hole and the first main spindle screw hole and is threaded to a main spindle of external equipment, wherein the converging disc and the grinding tool are locked to the external equipment.
 27. The tool-cooling mechanism according to any one of claims 1-17 and 19-25, wherein the grinding tool is a trepanning drill, a cup grinding wheel, a disc grinding wheel or an annular grinding disc. 